The present invention relates generally to improvements in abrading and polishing apparatus and it relates more particularly to an improved tumbling apparatus which is highly useful in the abrading, polishing and finishing of stones, minerals and similar materials.
A common procedure in the abrading, polishing and finishing of irregularly shaped objects, for example, stones and minerals in lapidary practice, both professional and amateur, is to tumble the objects with a suitable abrasive composition in the barrel of a tumbling apparatus. The conventional tumbling apparatus in which the tumbler barrel generally rotates only about its central longitudinal axis possesses numerous drawbacks and disadvantages. They are highly inefficient and uneconomical in operation and are very highly time consuming in achieving a suitable amount of abrasion and polish. It has been found that the rate of abrasion is sharply increased by imparting to the rotating tumbler barrel a rocking action about a transverse axis. While such rocking action is highly desirable, however, the mechanisms heretofore available for achieving such rocking actions are complex, expensive, highly power consuming and tumbling apparatus employing such mechanisms are difficult and inconvenient to load and unload, are of low power efficiency and otherwise leave much to be desired.